JPA/JPQL-批量更新 [英] JPA / JPQL - bulk update

问题描述

我必须在一个表上执行批量更新. 作一个简单的例子:

I have to perform a bulk update on a table. Making a fast example :

 UPDATE Book b SET b.amount = b.amount + 1 WHERE b IN ( :books )

问题是b.amount可以是或NULL值或int，如果存在NULL值，则应表现为b.amount等于1.

The problem is that b.amount can be or a NULL value or an int, and if there is a NULL value it should behave as b.amount would be equal to 1.

JPA/JPQL中是否有任何广播"或其他方法可以解决此问题，

Is there any "cast" in JPA/JPQL or any other way to work-around this problem,

先谢谢您

关于， P

推荐答案

您应该可以使用COALESCE:

UPDATE Book b SET b.amount = COALESCE(b.amount, 1) + 1 WHERE b IN ( :books ) 

这篇关于JPA/JPQL-批量更新的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！